What distinguishes a web application firewall from a network firewall?

1 What is a network firewall?

A network firewall is a device or software that monitors and controls the incoming and outgoing traffic between different networks or hosts. It acts as a barrier that blocks or allows traffic based on predefined rules or policies. A network firewall can protect web applications from unauthorized access, network attacks, and malicious traffic at the network layer. However, a network firewall cannot inspect or filter the content or logic of the web applications, which may contain vulnerabilities or flaws that can be exploited by hackers or bots.

2 What is a web application firewall?

A web application firewall is a specific type of firewall that focuses on the application layer. It analyzes and filters the HTTP requests and responses between web applications and clients. It can detect and prevent common web application attacks, such as cross-site scripting (XSS), SQL injection, and remote file inclusion. A web application firewall can also protect web applications from bots, scrapers, and denial-of-service (DoS) attacks. A web application firewall can be implemented as a hardware appliance, a software module, or a cloud service.

3 How do WAFs and network firewalls work together?

WAFs and network firewalls are not mutually exclusive, but rather complementary. They can work together to provide a layered defense for web applications. A network firewall can filter out unwanted or malicious traffic at the network layer, while a WAF can inspect and block harmful requests or responses at the application layer. By combining WAFs and network firewalls, web applications can achieve higher levels of performance and security, as well as comply with various standards and regulations.

4 Why are WAFs and network firewalls important for web testing?

WAFs and network firewalls are essential for web testing as they can identify and address the risks and vulnerabilities of web applications. Web testing encompasses various activities, such as functional testing, usability testing, performance testing, and security testing. WAFs and network firewalls can provide visibility by monitoring and logging the traffic and activity of web applications, allowing web testers to analyze and troubleshoot issues, measure performance, and generate reports. Additionally, they can protect web applications from attacks that may compromise their functionality, availability, and integrity. WAFs and network firewalls can also help simulate and test different attack scenarios and responses. Finally, they can ensure that web applications meet the requirements of organizations or regulations such as PCI DSS, HIPAA, GDPR, or OWASP. This way, web testers can audit and verify the compliance status of web applications.

5 How to choose the right WAF and network firewall for web testing?

When selecting a WAF and network firewall for web testing, web testers should consider several factors, such as the size, complexity, and nature of the web applications, the budget and resources available, and the specific goals and needs of the web testing process. To ensure that they make an informed decision, web testers should ask themselves questions like: what are the main threats and vulnerabilities that affect the web applications? What are the performance and security objectives and metrics of the web testing process? What features and functions should the WAF and network firewall provide? How easy or difficult is it to install, configure, and maintain them? And how compatible and scalable are they with the web applications and the testing environment? By answering these questions, web testers can compare different WAFs and network firewalls and choose the ones that best meet their needs.